Ken Caldeira on geoengineering as contingency

In testimony before the British Parliament, Ken Caldeira has done a good job of expressing what I consider to be the appropriate perspective on geoengineering: the deliberate modification of the climate system, intended to counteract anthropogenic climate change. While it may well be possible to reduce the degree of temperature increase – or even reduce atmospheric levels of greenhouse gasses – though geoengineering, it seems nearly certain that doing so will produce harmful and unintended effects. There is also the danger that simply exploring the prospect of geoengineering will encourage us to use it as a perceived quick fix, rather than actually reducing greenhouse gas emissions.

Those things being said, there is a strong counter-argument. We know from the paloeclimatic record that there have been times in history when climate changed violently, over the span of decades. We also know that we are pushing the climate system farther and farther from the equilibrium it was at prior to the Industrial Revolution. As such, the risk of abrupt or runaway climate change is very real and potentially catastrophic. This is especially true if the climate system is actually as sensitive as climatologist James Hansen has suggested in his recent work.

For the sole purpose of having a fall-back if disaster seems imminent, it seems sensible to investigate possible geoengineering technologies, assessing them in terms of probable effectiveness, secondary consequences, and overall risks. As Caldeira explains:

“Only fools find joy in the prospect of climate engineering. It’s also foolish to think that risk of significant climate damage can be denied or wished away. Perhaps we can depend on the transcendent human capacity for self-sacrifice when faced with unprecedented, shared, long-term risk, and therefore can depend on future reductions in greenhouse gas emissions. But just in case, we’d better have a plan.”

If we find ourselves suddenly on the cusp of the disintegration of Greenland or West Antarctica, the abrupt drying and burning of the Amazon, or the failure of the Asian monsoon, we may find ourselves glad to have conducted this research in advance, even if the ultimate result of that research is the knowledge that geoengineering is actually technically impossible or unacceptably risky. Better to learn that in advance than to roll the die at a time when no room for deliberation remains.

[W]e may find ourselves glad to have conducted this research in advance, even if the ultimate result of that research is the knowledge that geoengineering is actually technically impossible or unacceptably risky.

This makes sense, though there is definitely a danger of feeding the implicit general expectation that technology will deal with climate change in a relatively painless way – at least for those living in the developed world.

I agree about the risk of complacency, but I don’t think researching geoengineering is overly likely to make it worse. In my experience, most technological optimists have a general faith in innovation, not a hope rooted in one or another particular technology. In the absence of geoengineering research, they would just focus on nuclear fusion, air capture of carbon dioxide, and so forth.

I see geoengineering research as a bit like research into how to deflect a comet or asteroid: something that you very much hope you will never need to use, but recognize that you need to have ready should the feared situation arise.

My biggest objection is to taking emission reductions from CCS as a given, as plans like that of the Government of Alberta do. CCS is nearly as speculative as geoengineering, when it comes to its cost-effective ability to reduce emissions at an acceptable level of risk.

A secondary objection concerns subsidy. There aren’t huge established firms in businesses where geoengineering could directly ‘ride to the rescue.’ In the case of the coal industry, that is very much the hope for CCS. Whereas funding basic research into geoengineering doesn’t particular privilege one commercial interest over another, CCS subsidies directly assist the firms that are doing the most to increase global greenhouse gas concentrations.

That being said, I don’t oppose CCS research in principle. It was specifically recommended in the Joint Statement of the national science academies of the G8 countries and Brazil, China, India, Mexico and South Africa. If CCS proves effective and cost-competitive, it will be great news. It will reduce the challenge of finding new sources of energy; reduce the danger associated with the big coal reserves in the US, China, and elsewhere; and provide an opportunity to generate negative net emissions, when used with plants fuelled on biomass.

With serious talk about geoengineering options now on a serious roll (“Not so sotto voce any more” is how RealClimate put it back in August) 80 climate researchers have been polled by the Independent about whether we should prepare techno-fixes such as ocean fertilization or aerosol clouds as an emergency lever on the Earth system.

The paper reports today that 54% – i.e. 43 of them – think we should draw up such plans. Here’s the actual poll question – not reprinted by the Independent, but reproduced by a recipient (via the geoengineering Google Group):

“Do you agree that we now need a “Plan B” whereby a geoengineering strategy – research, development and possible implementation – is drawn up in parallel to a treaty to reduce carbon emissions (subject to international agreements and a scientific assessment of risk)?”

ofcourseyouare writes “The Independent is a UK newspaper which has been pushing hard for cuts in CO2 emissions for years. It recently polled a group of ‘the world’s leading climate scientists,’ revealing a ‘growing support for geoengineering’ in addition to cutting CO2 — not as a substitute. For example, Jim Lovelock, author of The Gaia Theory, comments: ‘I disagree that geoengineering the climate is a dangerous distraction and I disagree that on no account should it ever be considered. I strongly agree that we now need a “plan B” where a geoengineering strategy is drawn up in parallel with other measures to curb CO2 emissions.’ Professor Kerry Emanuel of MIT said, ‘While a geoengineering solution is bound to be less than desirable, the probability of getting global agreement on emissions reductions before it is too late is very small.'”

Why do I think those attempts will change the world? Geoengineering is not, after all, a panacea. It cannot precisely cancel out the effects of greenhouse gases, and it is likely to have knock on effects on the hydrological cycle which may well not be welcome. Even if the benefits outweigh the costs, the best-case outcome is unlikely to be more than a period of grace in which the most excessive temperature changes are held at bay. Reducing carbon-dioxide emissions will continue to be necessary. In part that is because of the problem of ocean acidification, and in part because a lower carbon-dioxide climate is vastly preferable to one that stays teetering on the brink of disaster for centuries, requiring constant tinkering to avoid teetering over into greenhouse hellishness.

So geoengineering would not “solve” climate change. Nor would it be an unprecedented human intervention in the earth system. It would be a massive thing to undertake, but hardly more momentous in absolute terms than our replacement of natural ecosystems with farmed ones; our commandeering of the nitrogen cycle; the wholesale havoc we have wrought on marine food webs; or the amplification of the greenhouse effect itself.

But what I see as world changing about this technology is not the extent to which it changes the world. It is that it does so on purpose. To live in a world subject to purposeful, planetwide change will not, I think, be quite the same as living in one being messed up by accident. Unless geoengineering fails catastrophically (which would be a pretty dramatic change in itself) the relationship between people and their environment will have changed profoundly. The line separating the natural from the artificial is itself an artifice, and one that changes with time. But this change, different in scale and not necessarily reversible, might finish off the idea of the natural as a place or time or condition that could ever be returned to. This would not be the “end of nature” — but it would be the end of a view of nature that has great power, and without which some would feel bereft. The clouds and the colours of the noon-time sky and of the setting sun will feel different if they have become, to some extent, a matter of choice.

The problem is in some ways pretty obvious: No one knows whether geoengineering can really be made to work. As Keith pointed out, even for the best characterised putative intervention — a stratospheric aerosol like those produced by volcanoes — the comparatively cursory research to date has turned up a wealth of complexities that have not yet been addressed by proponents, and more research will turn up even more of them. To Keith and Caldeira, this raises a nightmare scenario: that the world will have in the back of its mind that geoengineering is there as a fallback, will find that it needs a fallback, and will then find out that the fallback is not there in any practical sense. On this basis the sooner it is clear that there is no way out the better: time to do some serious research.

Fertilizing the oceans ? Areosol clouds ? Are any of you aware of the quantities needed for such measures to have any effect ? Or the implications on the living environment? There is a common word for this – pollution. At the required levels the industrial revolution will seem rather trivial. Seems to me that geoengineers know how to calculate abiotic factors but lack basic understanding of biology and ecosystems.

Preserving nutrients on land by way of reducing soil erosion and agricultiral / industrial runoff has been the key objective for decades. This practice is based on solid knowledege of how excess nutrients damage aquatic life. In the same way, the devastating effects of acid rain on forests have been studied over time in areas with local pollution. The remedy was simply to filter the pollution at its source – not at all spectacular but very effective.

Keep it simple and realistic! The only way to reduce human induced climate changes is to reduce emission of greenhouse gases. As effective as it is intellectualy boring. And yes, CCS is definitely part of the solution, the same way technical inventions was in solving nutrient runoff and acid rain problems.

Seems to me the principal challenge now will be to keep “geotamperers” away from actually realizing any of those nutty ideas. It is well known that humanity have an ugly record of leaving influence and politics to extremists.